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Turbulent boundary layers and hydrodynamic flow analysis of nanofluids over a plate

Journal of Central South University 2021年第11期28卷 3340-3353页

作者： AOUINET Hana DHAHRI maher SAFAEI mohammad reza SAmmOUDA Habib ANQI Ali E. Higher Private School of Engineering and Applied Technology(IHE-ESPITA) SousseTunisia Laboratory of Energy and materials(LabEm)(LR11ES34) High School of Sciences and Technology of Hammam SousseSousse UniversityBP 4011Hammam SousseTunisia Department of medical Research China Medical University HospitalChina Medical UniversityTaiwanChina mechanical Engineering Department Faculty of EngineeringKing Abdulaziz UniversityJeddahSaudi Arabia Department of mechanical Engineering College of EngineeringKing Khalid UniversityAbha 61421Saudi Arabia Research Center for Advanced materials Science(RCAmS) King Khalid UniversityAbhaSaudi Arabia

A numerical analysis of the log-law behavior for the turbulent boundary layer of a wall-bounded flow is performed over a flat plate immersed in three nanofluids(Zn O-water,SiO_(2)-water,TiO_(2)-water).Numerical simulations using CFD code are employed to investigate the boundary layer and the hydrodynamic *** validate the current numerical model,measurement points from published works were used,and the compared results were in good *** were carried out for the velocity series of 0.04,0.4 and 4 m/s and nanoparticle concentrations0.1% and 5%.The influence of nanoparticles’ concentration on velocity,temperature profiles,wall shear stress,and turbulent intensity was *** obtained results showed that the viscous sub-layer,the buffer layer,and the loglaw layer along the potential-flow layer could be analyzed based on their curving quality in the regions which have just a single wall *** was seen that the viscous sub-layer is the biggest area in comparison with other ***,the section where the temperature changes considerably correspond to the thermal boundary layer’s thickness goes a downward trend when the velocity *** thermal boundary layer gets deep away from the leading ***,a rise in the volume fraction of nanoparticles indicated a minor impact on the shear stress developed in the *** all cases,the thickness of the boundary layer undergoes a downward trend as the velocity increases,whereas increasing the nanoparticle concentrations would enhance the *** precisely,the log layer is closed with log law,and it is minimal between Y^(+)=50 and Y^(+)=*** temperature for nanoparticle concentration φ=5%is higher than that for φ=0.1%,in boundary layers,for all studied ***,it is established that the behavior is inverted from the value of Y^(+)=1 and the temperature for φ =0.1% is more important than the case of φ =5%.For turbulence intensity peak,this peak exists at Y^(+)

关键词： turbulent boundary layers nanofluids hydrodynamic flow wall shear stress turbulent intensity

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远视与角膜地形图(英文)

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国际眼科杂志 2009年第3期9卷 417-419页

作者： masoud reza manaviat mohammad reza Besharati maryam Kheirandish maryam Dehyadegari 伊朗亚兹德Shahid Sadoughi大学眼科

目的:运用OrbscanII测量远视者角膜地形图。方法:回顾性,观察性,连续性临床病例研究,进行LASIK术前评估的远视患者共295眼。回顾分析患者的年龄、性别以及OrbscanII所得角膜地形图。屈光度及以下参数由OrbscanII系统所得:角膜厚度、角... 详细信息

目的:运用OrbscanII测量远视者角膜地形图。方法:回顾性,观察性,连续性临床病例研究,进行LASIK术前评估的远视患者共295眼。回顾分析患者的年龄、性别以及OrbscanII所得角膜地形图。屈光度及以下参数由OrbscanII系统所得:角膜厚度、角膜直径、瞳孔直径和前房深度。结果:总的平均角膜厚度为546.3±35.5μm,17～29岁年龄组547.3±38.4μm,30～44岁年龄组553.4±38.3μm,45岁以上年龄组546.2±29.3μm。女性平均角膜厚度为551.5±35.9μm,男性为542.6±34.7μm。总的平均前房深度为2.57±0.40mm,17～29岁年龄组2.82±0.39mm,30～44岁年龄组2.49±0.39mm,45岁以上年龄组2.37±0.40mm。女性平均前房深度2.53±0.40mm,男性为2.60±0.40mm。角膜厚度与角膜曲率之间存在显著负相关关系(P=0.005,r=0.16),与瞳孔直径存在相关关系(P=0.013,r=0.144)。屈光不正严重度与前房深度负相关,与角膜曲率负相关(P=0.061,r=0.108)。结论:本研究提供并分析了远视患者的OrbscanII测量数据,远视患者的平均角膜厚度为546.3±35.5μm,平均前房深度为2.57±0.40mm。

关键词： Orbscan II 角膜地形图远视

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The First Eccentric Zagreb Index of Linear Polycene Parallelogram of Benzenoid

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Open Journal of Applied Sciences 2016年第5期6卷 315-318页

作者： mehdi Alaeiyan mohammad reza Farahani muhammad Kamran Jamil m. R. Rajesh Kanna Department of mathematics of Iran University of Science and Technology (IUST) Tehran Iran Department of mathematics Riphah Institute of Computing and Applied Sciences (RICAS) Riphah International University Lahore Pakistan Department of mathematics Maharani’s Science College for Women Mysore India

Let G = (V,E) be a graph, where V(G) is a non-empty set of vertices and E(G) is a set of edges, e = uv∈E(G), d(u) is degree of vertex u. Then the first Zagreb polynomial and the first Zagreb index Zg1(G,x) and Zg1(G) of the graph G are defined as Σuv∈E(G)x(du+dv) and Σe=uv∈E(G)(du+dv) respectively. Recently Ghorbani and Hosseinzadeh introduced the first Eccentric Zagreb index as Zg1*=Σuv∈E(G)(ecc(v)+ecc(u)), that ecc(u) is the largest distance between u and any other vertex v of G. In this paper, we compute this new index (the first Eccentric Zagreb index or third Zagreb index) of an infinite family of linear Polycene parallelogram of benzenoid.

关键词： molecular Graph Linear Polycene Parallelogram of Benzenoid Zagreb Topological Index Eccentricity Connectivity Index Cut method

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Effect of fluoride treatment on corrosion behavior of mg-Ca binary alloy for implant application

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Transactions of Nonferrous metals Society of China 2013年第3期23卷 699-710页

作者： Hamid reza Bakhsheshi-Rad mohd Hasbullah Idris moha mmed Rafiq Abdul Kadir mohammadreza Daroonparvar materials Engineering Department Faculty of Mechanical EngineeringUniversiti Teknologi MalaysiaSkudai 81310JohorMalaysia Department of Biomechanics & Biomedical materials Faculty of Biomedical Engineering & Health SciencesUniversiti Teknologi MalaysiaSk udai 81310JohorMalaysia

The influence of hydrofluoric acid（HF） treatment on the corrosion behavior of the mg-0.5Ca alloys was investigated by immersion specimen in sodium hydroxide and HF solutions with various concentrations and durations at room *** evolutions of the specimens were characterized by atomic force microscopy,X-ray diffraction,field-emission scanning electron *** corrosion resistance was examined through potentiodynamic polarization and immersion test in Kokubo *** results revealed that the fluoride treated mg-0.5Ca alloys produced by immersion in 40% HF provided more uniform,dense and thicker coating layer（12.6 μm） compared with the 35% HF treated *** electrochemical test showed that the corrosion resistance of fluoride treated specimen was 35 times higher compared with the untreated mg-0.5Ca alloy specimen in Kokubo *** vitro degradation rate of the fluoride treated specimens was much lower than untreated mg-0.5Ca alloy in Kokubo *** immersion test the surface of 40% HF treated sample showed a few corrosion dots,while untreated specimens were fully covered by corrosion products and *** treated mg-0.5Ca alloy with 40% HF is a promising candidate as biodegradable implants due to its low degradation kinetics and good biocompatibility.

关键词： mg-Ca alloy surface treatment corrosion behavior biocompatibility

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Omega and Cluj-Ilmenau Indices of Hydrocarbon molecules “Polycyclic Aromatic Hydrocarbons PAHk”

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Computational Chemistry 2016年第4期4卷 91-96页

作者： m. R. Rajesh Kanna R. Pradeep Kumar muhammad Kamran Jamil mohammad reza Farahani Department of mathematics Maharani’s Science College for Women Mysore India Department of mathematics The National Institute of Engineering Mysuru India Department of mathematics Riphah Institute of Computing and Applied Sciences (RICAS) Riphah International University Lahore Pakistan Department of Applied mathematics Iran University of Science and Technology (IUST) Tehran Iran

A topological index is a numerical value associated with chemical constitution for correlation of chemical structure with various physical properties, chemical reactivity or biological activity. In this paper, we computed the Omega and Cluj-Ilumenau indices of a very famous hydrocarbon named as Polycyclic Aromatic Hydrocarbons PAHk for all integer number k.

关键词： molecular Graph Hydrocarbons Topological Indices

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Analysis and identification of the hidden relationships between effective factors in the mortality rate caused by road accidents: A case study of Fars Province, Iran

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Chinese Journal of Traumatology 2019年第4期22卷 233-239页

作者： Saeed Lotfi Ali reza Honarvar Saeid Gholamzadeh Department of Information Technology and Computer Engineering Safashahr Branch Islamic Azad University Safashahr Iran Legal medicine Research Center Legal Medicine Organization Tehran Iran

Purpose: An analysis and identification of the hidden relationships between effective factors in the mortality rate caused by road accidents in Fars Province of Iran to prevent and reduce traffic accidents in the future. methods: This cross-sectional study was conducted to integrate all the pervious researches performed on mortality rate of road traffic accidents in Fars Province from march 21,2013 to march 20,2017. In order to reveal the relationships between the factors affecting mortality rates of road traffic accidents, the data regarding road traffic accidents extracted from resources such as Legal medicine Organization, Traffic Police, Accident & Emergency Department, as well as Department of Roads and Urban Development of Fars Province, then cleaned and the applicable attributes embedded in the data all aggregated for further analysis. It should be noted that the data not related to Fars Province were deleted, the data analyzed, converted and the aggregation between various attributes identified. The aggregation between these different attributes as well as the FP-growth algorithm and two indexes of support and confidence calculated and interesting and effective rules extracted. In the end, several accident-p「ovoking factors, the degree of consecutive and interdepende nee of each one in road accide nts identified and in traduced. The statistical analysis was conducted by using Rapid miner software. Results: Of the 6216 people dead due to road traffic accidents, 4865 (79.02%) were male and 1292 (20.98%) were female, 59 of them have no clear gender. The largest portion of people died of road traffic accidents belonged to married and self-employed men who collided with motorcycles in autumn. moreover, young individuals (aged 19-40 years) w让h secondary educational level who died of accidents in summer at 12:00 a.m. and then 5:00 p.m. in outer city main roads of Kazerun-Shiraz, then Darab- Shiraz, Fasa-Darab and in within-city main streets had the highest mortalit

关键词： Road traffic accidents mortality Vehicle Fars province Iran

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Relativistic Schrodinger Wave Equation for Hydrogen Atom Using Factorization method

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Open Journal of microphysics 2013年第1期3卷 1-7页

作者： mohammad reza Pahlavani Hossein Rahbar mohsen Ghezelbash Department of Physics Faculty of sciencesUniversity of MazandaranBabolsarIran

In this investigation a simple method developed by introducing spin to Schrodinger equation to study the relativistic hydrogen atom. By separating Schrodinger equation to radial and angular parts, we modify these parts to the associated Laguerre and Jacobi differential equations, respectively. Bound state Energy levels and wave functions of relativistic Schrodinger equation for Hydrogen atom have been obtained. Calculated results well matched to the results of Dirac’s relativistic theory. Finally the factorization method and supersymmetry approaches in quantum mechanics, give us some first order raising and lowering operators, which help us to obtain all quantum states and energy levels for different values of the quantum numbers n and m.

关键词： Relativistic Schrodinger Wave Equation Factorization method Ladder Operators Supersymmetry Spin

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mechanical properties,corrosion behavior and biocompatibility of orthopedic pure titanium−magnesium alloy screw prepared by friction welding

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Transactions of Nonferrous metals Society of China 2020年第11期30卷 2952-2966页

作者： mojtaba Sadeghi GOGHERI masoud KASIRI-ASGARANI Hamid reza BAKHSHESHI-RAD Hamid GHAYOUR mahdi RAFIEI Advanced materials Research Center Department of Materials EngineeringNajafabad BranchIslamic Azad UniversityNajafabadIran

The dissimilar joining of biodegradable magnesium alloy to pure commercial titanium by rotational friction welding with rotational speeds of 1100,1200 and 1300 r/min for the production of bio-screw was *** metallographic analysis revealed that a good joining was obtained at the Ti/mg alloy *** the magnesium alloy side,various regions such as the weld center zone(WCZ),dynamic recrystallization zone(DRX),thermo-mechanically affected zone(TmAZ)and partially deformed zone(PDZ)were *** highest tensile and shear strengths were 173 and 103.2 mPa,respectively at a rotational speed of 1300 r/*** Ti/mg alloy dissimilar friction welded joint failed at the vicinity of the intermetallic zone containing Ti3Al *** hardness values from the base metal magnesium alloy to the joining point increased mainly due to grain refinement(8.57μm in diameter)and the presence of titanium particles,while the hardness values were constant on the titanium *** was also found that the corrosion rate of the Ti/mg alloy joint was higher compared with that of the Ti and mg alloy from the immersion ***,the sample with a rotational speed of 1300 r/min showed better biocompatibility and a cell viability of 98.12%due to better corrosion resistance.

关键词： mg alloy pure commercial titanium friction welding shear strength biodegradability

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Determination of Some Design Parameters for Roller Type Seed metering Device

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Journal of Agricultural Science and Technology(A) 2012年第6期2卷 845-850页

作者： Hossein Navid Hamid reza Ghassemzadeh mohammad moghaddam Department of Agricultural machinery Engineering University of Tabriz Tabriz lran Department of Agronomy and Plant Breeding University ofTabriz Tabriz Iran

There are many design parameters in precision planters to be considered such as cell diameter, peripheral speed of roller, number of cells, manner of feeding seeds into cell and travel speed. In precision planters each cell must contain only one seed. Therefore, sliding the seed to the cell is important and depends on several parameters such as seed repose angle, seed dimensions and physics of cell. To help the seed to repose in the cell, making a groove on the roller would be very useful. Dimensions of this groove are very important and are considered as basic design parameters. This research was performed to determine some design parameters such as roller speed, travel speed, length and depth of groove for tomato seeds precision planting. In this regard, seeds with a diameter of 4 mm were used. The range of variation was based on calculations obtained. A roller with 42 mm width, 118 mm diameter and 15 cells on the surface was used in the experiment. For each cell, a triangular groove was created on the roller. The groove depth varied from zero at the beginning to the maximum value where the groove connected to the cell. The test unit had a continued and wide belt with 1 l m length. In each replication, planter worked for 20 s to reach a stable state. Thereafter, seeds were allowed to drop on the grease belt. Number of seeds and their spacing were measured on the 4.5 m of the belt. Results showed that the roller speed of 41.5 rpm, the planter travel speed of approximately 1 km/h, groove length of 6-8 mm and groove depth of 1.5 mm can improve planter performance for tomato pelleted seed.

关键词： Design metering device precision planter design parameters

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Optimization of a Dual-Baffled Rectangular Tank Against the Sloshing Phenomenon

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Journal of marine Science and Application 2022年第1期21卷 116-127页

作者： Hassan Saghi Dezhi Ning Shunqi Pan reza Saghi Department of Civil Engineering Hakim Sabzevari UniversitySabzevar ***Iran State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Hydro-environmental Research Centre School of EngineeringCardiff UniversityCardiff CF243AAUK mSc of Hydraulic engineering Mashhad BranchIslamic Azad UniversityMashhad ***Iran

A dual-baffled rectangular tank with different configurations is proposed to reduce the sloshing effect,and design optimization is conducted through numerical simulations with open-source software,namely OpenFOAm,based on the computational fluid dynamic model.A series of physical experiments in the dual-baffled rectangular tank is performed for model validation and design optimization with the measured water surface elevation distributions along the *** optimization uses the calculated maximum horizontal force exerted on the tank and entropy generation(EG)as the *** show that the dual-baffle configuration positioned at the tank center is more effective in reducing the sloshing than that of the single baffle when the relative baffle height and initial water depth ratio(Hb/Hw,where Hb and Hw represent baffle height and static water depth,respectively)are larger than ***,such an effect then diminishes when the ratio is larger than *** effect of the dual-baffle configuration on the sway motion under the condition of different motion amplitudes and frequencies is also *** results show that the reduction in the maximum horizontal force is almost the same for dual-and single-baffled configurations and reaches the minimum when the sway motion amplitude is near 0.03 *** dual-baffled configuration for the angular frequency of the sway motion is more effective than the single-baffled in reducing the sloshing at the low angular frequencies but is only less effective at high angular ***,the optimal baffle inclination angle is 85°when the inclined straight and curved baffles are used,and curved baffles can successfully decrease the horizontal force exerted on the tank and EG.

关键词： Rectangular storage tank Dual-baffled rectangular tank Sloshing phenomenon Optimization Horizontal force Entropy generation

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